Answered: Defense Around Climbing Zone

My team has built a lifter that we are planning on using in our next competition. In preparation we have been thinking about possible defense other teams may attempt. In order to prevent teams from blocking us, we have a high-torque drive, and so can push others around, but not move around them.
In thinking of possible scenarios I thought of the following one, and was wondering about a ruling in this case.
this document contains pictures describing this scenario

our partner is waiting for us in the climbing zone, during the last 30 seconds of the match, and we are making our way to the zone, but an opponent sits in our way. We are not fast enough to go around them so we simply shove them.

In doing so we push them into our climbing zone, where they block us from climbing. I understand that they would not be penalized for entering our climbing zone, because we pushed them there. However the question then becomes, assuming they are able, is our opponent required to immediately vacate our climbing zone. Or, would it be legal for our opponents, to sit there, in our climbing zone during the last 30 seconds of the match and block us from climbing. this is all assuming they are able to leave if they wanted.

Thanks in advanced for your help

They must leave immediately to avoid violating <SG11>.